SOLVED: Date Formatting within CSV file

Have worked out the CSV import feature nicely discovering the published field had to be formatted as a number to get Active working as number 1 etc. Also found we cannot import into List fields so deleted my lists then did the import and that worked.
Only issue now is the date formatting - I need all end dates to be 2016-31-03 and have tried formatting the column in the csv file as text, a number and a date but think I'm now going round in circles. Dates are all importing as today's date.
Can you please advise what I might have done wrong?
Thanks in advance!

SOLVED: Field needs to be formatted as a date but in US combination (I'm in Australia) i.e. 2016-03-31
Spend 2 hrs trying to work it out, put a post up and solve it 5 minutes later!!!!

. Thanks for the update.